There has been extensive prior art activity in the pursuit of averting the use of on-floor conduits for conveying electrical power and telephone or communication lines to floor locations which were not within the original architectural and electrical planning of a facility, such as a multi-floor concrete building. Such on-floor conduits are in the first place aesthetically unpleasant and secondly can give rise to personnel danger, such as by tripping over the same.
While the art has averted these problems in the introduction of flat undercarpet cable installations, the problem remains extant in the use of the conventional discrete wiring systems in place in general in existing buildings and for currently-planned facilities in which the undercarpet approach is not elected.
In the conventional discrete installations, the problem under discussion has been addressed by drilling a passage through the concrete floor and conducting power and/or communication signals from an under floor to the floor in which a new power and/or communication signal outlet is desired. Electrical safety codes have place two sanctions on such activity. Firstly, it is essential that the installed transition apparatus not function as a chimney or fire-advancing flue in the event of fire occurrence on the lower floor. Secondly, it is imperative that the transition apparatus not function as a conductive heat channel between floors. The industry has largely met these requirements through the use of intumescent material in the transition apparatus, such material expanding under fire conditions against the concrete circumscribing the passage to effectively block the pre-existing flue which may have been present in the passage. Further, the art has reached structures which have conductive heat blocking members, i.e., synthetic spacers, disposed axially between and separating conductive heat communication between heat conductive members of the apparatus.
Occasions arise where installed such apparatus becomes superseded by new power/communication facility layout needs. Here, one abandons prior inter-floor transition apparatus and looks to drill new passages through the concrete floor and to install new transition apparatus. Typically, the art has left the prior transition apparatus in place, with its satisfaction of the two industry requirements, and has installed a so-called "abandonment plate" or the like over the in-place apparatus. This practice has the adversity of the leaving of a relatively expensive and otherwise usable component in place with the requirement for new transition apparatus to be provided for the new installation.